Matchday 3 will be played today and tomorrow (break on Sunday for the Nations League final) with Matchday 4 taking place Monday-Tuesday. Won't go through all the games today but here are some of the key fixtures
A: Czech Rep vs. Bulgaria, Montenegro vs. Kosovo
In a group which England is expected to breeze games like these will likely determine the runners-up, Czechs looking to rebound from their hammering at Wembley while Bulgaria are unbeaten with two draws. Montenegro-Kosovo would have been an interesting 'derby' type match but its being played behind closed doors. Kosovo are on a high at the moment and haven't lost a match since WCQ in October 2017
B: Ukraine vs. Serbia
One of the more important matches today, both these teams come off impressive draws in Portugal but a Ukraine win will already put them one foot at the Euro defeating a direct rival for the automatic qualifying spots. For Serbia it's a weird start having played their two toughest matches (Portugal and Ukraine away) in the first two rounds. I however see this as a 0:0, low-risk draw game
D: Denmark vs. Rep of Ireland
5th competitive fixture between these two since November 2017, three of the four previous games were 0:0 draws with the only victory being the decisive 5:1 win by Denmark in Dublin in the WC playoff. Ireland have a perfect start but this is their first test, Denmark had that impressive come from behind draw in Basel last matchday
F: -
Spain and Sweden both face the group minnows, Norway vs. Romania doesn't excite the neutral but on a result basis its an important game for Norway who will be chasing the pack if they lose today
G: Austria vs. Slovenia
Probably the most equal group but not the most interesting games, Poland perfect so far but they go to Macedonia which is always a difficult place to play. Big pressure on Austria to get a result against Slovenia after losing their first two matches